Covid-19-related hospitalizations fall when states require masks and other face coverings, the Centers for Disease Control and Prevention reported Friday.
The CDC analysis of the effect of mask mandates in 10 states found that such requirements led to a decline of 5.5 percentage points in hospitalization growth rates, compared with data from the month before the mandate. The directives called for people to wear coverings over their mouths and noses outside their home, and especially in restaurants and retail businesses.
States included in the report were California, Colorado, Connecticut, Maryland, Michigan, Minnesota, New Mexico, New York, Ohio and Oregon.
The CDC found that weekly hospitalization rates declined by 2.9 percentage points among adults between the ages of 40 and 64 during the first two weeks after implementation of mandates. After at least three weeks, the decline grew to 5.5 percentage points among all adults under age 65.
"SARS-CoV-2, the virus that causes [Covid-19], is transmitted predominantly by respiratory droplets generated when infected persons cough, sneeze, spit, sing, talk, or breathe," the study authors wrote, adding that masks are part of a "multipronged strategy to decrease exposure to and transmission of SARS-CoV-2 and reduce strain on the health care system."
Data included in the new report was collected from March to October 2020. President Joe Biden recently issued an executive order requiring that people wear masks while on federal property. The CDC followed shortly after with a directive that anyone using public transportation must also wear a mask.
New Covid-19 cases continue to decline. "The number of new cases on February 3 of approximately 121,000 represents a 61 percent decrease since the peak on January 8," CDC director Dr. Rochelle Walensky said during a White House briefing with reporters on Friday.
What's more, "the number of new hospital admissions reported on February 2 — approximately 10,500 — was down nearly 42 percent since the hospitalization peak of 18,000 reported on January 5," Walensky said.
Still, it's too soon to draw a direct link between the recent federal mask mandates and the decline in Covid-19 cases and/or hospitalizations.
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"I do think a mask mandate is helping protect people," Walensky said. "But what also is happening is that we are coming off of the case bomb from the holidays," referring to the spike in cases following gatherings during Thanksgiving and Christmas.
Any decrease in hospitalizations is welcome news to those on the front lines of treating patients.
"If you decrease hospitalizations, you are no longer overwhelming health care systems," said Dr. Hugh Cassiere, director of critical care services for Sandra Atlas Bass Heart Hospital at North Shore University Hospital, part of Northwell Health, on Long Island, New York.
"That's important because you can still continue to take care of patients who come into the hospital for other types of medical diseases like pneumonia, heart attacks and strokes — things that were really neglected in some hospitals because there were no beds or no facilities to take care of those patients who needed care," he said.